Tropical Storm Michael has now officially become a hurricane, the US National Hurricane Centre said.
The storm off Mexico's Yucatan Peninsula has rapidly strengthened and is expected to strike the Gulf Coast in the Florida Panhandle with potential winds of 100mph.
Florida Governor Rick Scott has declared a state of emergency in 26 counties as the hurricane approaches the state.
Follow updates on Storm Michael below, as they happened.
Disaster agencies in all three countries reported deaths as roofs collapsed and residents were carried away by swollen rivers. Six people died in Honduras, four in Nicaragua and three in El Salvador. Authorities were also searching for a boy swept away by a river in Guatemala.
Most of the rain was blamed on a low-pressure system off the Pacific coast of El Salvador. Hurricane Michael in the Caribbean could have also contributed. The storms began Friday and were expected to dissipate Monday.
Residents in affected areas fled to government shelters and awaited help in more isolated areas. Rain also triggered landslides that blocked some highways in the region.
Hurricane Michael is the seventh named hurricane to have developed in the Atlantic Ocean this year, and is expected to become a Category 3 storm as early as Wednesday. The hurricane has continued churning towards the US mainland from Cuba on Monday afternoon.
A tropical weather system that rapidly strengthened into Hurricane Michael on Monday is likely to intensify ahead of an expected strike on Florida's Panhandle by midweek, forecasters said.
Michael could strengthen into a major hurricane with winds topping 111 mph (178 kph) by Tuesday night before an expected strike on the Panhandle or Big Bend, according to the National Hurricane Center.
Since the storm will spend two to three days over the Gulf, which has very warm water temperatures and favorable atmospheric conditions, "there is a real possibility that Michael will strengthen to a major hurricane before landfall," Robbie Berg, a hurricane specialist at the Miami-based storm forecasting hub, wrote in an advisory.
AP
Reports indicate several regions of Florida are expected to receive tropical downpours as Hurricane Michael makes landfall.
The storm was on a forecast track to pick up speed while heading north by Tuesday evening. Tropical storm force winds of up to 175 miles per hour were expected to extend on either side of the hurricane as it reached the Florida Panhandle.
After hitting Florida, the storm is forecast to move northeast on Wednesday and Thursday along the Atlantic Coast and batter the Carolinas, which are still recovering from Hurricane Florence last month.
BP Plc and Exxon Mobil Corp on Monday began evacuating personnel from Gulf of Mexico oil and gas production platforms.
The Commodity Weather Group said Michael was not likely to cause much interruption to oil and gas production.
The Gulf of Mexico is home to 17 percent of daily U.S. crude oil output and 5 percent of daily natural gas output, according to the U.S. Energy Information Administration.
More than 45 percent of the nation’s refining capacity is located along the U.S. Gulf Coast, which also is home to 51 percent of total U.S. natural gas processing capability.
Reuters
Florida Governor Rick Scott has tweeted the following message as Hurricane Michael is expected to make landfall, along with a photo of the governor meeting with emergency officials.
He wrote, “This morning I met with local officials and emergency management professionals in Bay County in preparation for Hurricane Michael. I will be in Pasco County this afternoon to give another briefing. FL families need to get ready for this storm RIGHT NOW.”
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Additional reporting from Reuters.
